This invention relates to a flight recorder used to provide information concerning the flight of a vehicle. In particular, the flight recorder is used to obtain data from the vehicle in order to provide and record accurate data during testing of the vehicle.
In certain applications, it is desired that a high degree of programmed guidance accuracy be accomplished without reliance on external information during flight of a vehicle. The accuracy of the guidance program must be assessed in order to determine the validity of the guidance program. The ability of external sensors, such as radar and photography, to determine such factors as vehicle attitude and speed does not meet accuracy requirements. For this reason, information concerning the vehicle's flight is recorded in flight during testing of the vehicle.
Further, for security reasons, it is important that the data contained in the flight recorder be incomplete and unuseable without other information and data which is not contained in the recorder.
Still further it is important that there be some flexibility in the sequence of events recorded during the test in order to monitor these events. For example, if the vehicle's mission is varied so as to change its flight during exercise of a manuever, it may be necessary to record data at times during a test other than the times contemplated during design of the test equipment.
Accordingly, it is an object of the invention to provide a flight recorder for an airborne vehicle which is able to inexpensively and reliably record flight information so that the performance of the vehicle can be determined with a high degree of precision and which can be modified in a simple and inexpensive fashion to modify the type of data being recorded during any particular part of the flight.
It is a further object of the invention to provide a flight recorder of the type described which contains information usable only with the benefit of additional information developed externally of the flight recorder.